Chemical process and composition



States This invention is directed to a new use for a known series of compounds; these known compounds are aryl sulfones utilized significantly, according to the present invention, as carriers in the process of dyeing a large assortment of hydrophobic fibers. Various other carriers are available but they do not show the economic and/or performance advantages of the aryl sulfone carriers as hereinafter described.

The inventor faced the problem of providing a carrier significantly better than those now available for use in the process of dyeing a variety of hydrophobic fibers. Such a carrier must exhibit the following properties and advantages: (1) It must have a very high boiling point in order to provide assurance of no fume problems. (2) It must not adversely affect the light fastness of dyes. (The carrier o-phenylphenol, for example, decreases the light fastness of some dyes.) (3) It must not filter out of the dyebath during the process of dyeing rawstock packages. (4) It must be economical, e.g., the dyebath solution employed is saturated with carrier, and the amount in solution must not be excessive. In addition, the prodnot itself should be relatively low in cost.

It is an object of the present invention to provide a novel process for dyeing numerous hydrophobic fibers. It is a further object of this invention to dye various hydrophobic fibers with a known series of compounds while utilizing aryl sulfone compounds as carriers. These and other obpects will become apparent in the following description and claims.

More specifically, the present invention is directed to the process of coloring hydrophobic fibers with disperse or cationic dyes from a hot aqueous dyebath by the aid of a carrier, the improvement being that which comprises using, as carrier, a sulfone compound free of watersolubilizing, ionogenic substituents, said sulfone compound being selected from the group consisting of:

(a) O Q I SO2 and 21 SO2-R Y wherein X is H, CH C 11 Cl, Br, OCT-l or --NHCOR', where R is CH or C H Y is H or CH and R is alkyl (C or The process of this invention is one wherein the heretofore described sulfone carrier may be utilized in an amount in excess of that which is sufficient to provide a saturated solution in the aqueous dyebath at the dyeing temperature utilized, normally from about 190 to 212 F. Representative preferred sulfone carriers are those containing at least one aryl ring, diaryl sulfones, symmetrical diaryl sulfones, and diphenyl sulfones. Preferred hydrophobic fibers include linear polyester fibers, acid-modified linear polyester fibers, cellulose triacetate fibers and acrylic fibers.

In a preferred embodiment of the present novel process there will be present from 0.1 to about 5% by Weight of said carrier of an anionic surfactant.

It is believed that the carriers of this invention cause a swelling of the fibers which opens up the fiber structure; in addition to this action, it is considered that the sulfones act as a mutual solvent for fiber and dye. The carrier which is present, after saturation is reached in the dyebath, is preferably in the form of a finely-divided solid during the dyeing process. Any melting to form globules of carrier would tend to cause spotty dyeing due to localized concentration of dye on the fiber at the location of the globules. However, the formation of carrier globules which tend to cause spotty dyeings is minimized by the use of emulsifying surfactants. Emulsifiers in the dyebath also serve to alleviate conditions that lead to serious spotting caused by the condensation of carrier vapors. This invention includes the use of aryl sulfones which melt under 100 C. and are present in liquid state in the hot dyebath. Said low melting carriers are prepared in dispersed form by vigorous mixing of molten sulfone with aqueous solutions of emulsifying agents. These hot emulsions form stable pastes upon cooling, which pastes are readily dispersed in the dyebaths as shown in Example 27. A more detailed description of the physical form of carriers may be found in US. Patent 2,833,613 (col. 1, lines 18-65) and The American Dyestuif Reporter, vol. 48, pages 23-24, November 2, 1959 and pages 3745, November 16, 1959.

The following described fibers are dyed avantageously by the process of this invention in the presence of sulfone carriers.

A. ACRYLIC FIBERS Defined by Textile World, in the ll/lan-MadeFiber Table1959 Revision, McGraw Hill Publishing (30., inc. 1959, as A manufactured fiber in which the fiberforming substance is any long-chain synthetic polymer composed of at least by weight of acrylonitrile units (1) Acrilan acrylic fiber made by Chemstrand Corporation.

(2) Creslan acrylic fiber made by American Cyanamid Company.

(3) The acid-modified acrylic fibers such as those described in US. 2,837,500 and US. 2,837,501.

(4) Zefran acrylic fiber made by the Dow Chemical Company.

B. MODACRYLIC FIBERS Defined by Textile World, loc. cit., as A manufactured fiber in which the fiber-forming substance is any long-chain synthetic polymer composed of less than 85% but at least 35% by weight of acrylonitrile units (1) Verel modacrylic fiber made by Tennessee Eastman Company.

C. NYTRIL FIBER Defined by Textile World, loc. cit., as A manufactured fiber containing at least 8% of a long-chain polymer of vinylidene dinitrile (--CH C(CN) where the vinylidene-dinitrile content is no less than every other unit in the polymer chain.

(1) Darvan nytril fiber developed by B. F. Goodrich Chemical Company.

3 D. ACETATE FIBERS Defined by Textile World, loc. cit., as A manufactured fiber in which the fiber-forming substance is cellulose acetate. Where not less than 92% of the hydroxyl groups are acetylated, the term triacetate may be used as a generic description of the fiber.

(1) Arnel triacetate fiber made by Celanese Corporation of America.

E. POYLESTER FIBERS Defined by Textile World, loc. cit, as A Manufactured fiber in which the fiber-forming substance is any long-chain synthetic polymer composed of at least 85% by weight of an ester of a dihydric alcohol and terephthalic acid (p-HOOCC H COOH).

(l) Polyethylene terephthalate fiber.

(2) The acid-modified polyethylene terephthalate fiber containing metal sulfonate groups as described more fully in Belgium Patent -No. 549,179, granted July 14, 1956.

(3) Kodel polyester fiber made by Tennessee Eastman Company and marketed by Eastman Chemical Products, Inc.

(4) Vycron polyester fiber of Beaunit Mills, Inc.

The dyeing procedure itself is illustrated in the following representative examples.

Example 1 A dyebath is prepared by mixing 1 part of the disperse orange dye obtained by coupling the diazo of p nitroaniline to N-(2-cyanoethyl)-N-methylaniline, 4 parts of a long chain saturated hydrocarbon sodium sulfonate surfactant, 2 parts of the condensation product of 20 moles of ethylene oxide with 1 mole of a C alcohol, 4 parts of the sodium salt of the condensation product of formaldehyde and 5,6,7,8 tetrahydro-Z-naphthalenesulfonic acid, and 4000 parts of water. The pH of the dyebath is adjusted to 5.0 by addition of acetic acid or sodium carbonate as required. 100 parts of a fabric of acid-modified polyester fiber (as defined in preceding section E-2) are prescoured for 20 minutes at 180 F. in 4000 parts of a solution containing 1 part of the sodium salt of the sulfate of the condensation product of ethylene oxide and oleyl alcohol, then rinsed and entered, while wet, into the dyebath. After dyeing at boiling temperature for 1.5 hours, the fabric is removed from the dyebath, rinsed, scoured at 200 F. for minutes with 4000 parts of a solution containing 1 part of the prescouring surfactant, thereafter rinsed in water and dried. The resulting dyeing is light orange in shade.

If a fabric of polyethylene terephthalate fiber is substituted in this example, a light orange dyeing is obtained.

Example 2 A dyebath is prepared in the manner described under Example 1, employing like ingredients and proportions. parts of a fine micropulverized powder of diphenyl sulfone are added to the dyebath as a carrier and stirred to form a uniform suspension of the powder. 100 parts of a fabric of acid-modified polyester fiber prescoured according to Example 1, are entered, dyed and aftertreated as in that example. The resulting dyeing is bright orange in shade and is six times as strong as the dyeing prepared in Example 1.

When a fabric of the unmodified polyethylene terephthalate fiber is used, instead of the acid-modified type in this example, a bright orange dyeing is obtained which is about four times as strong as that obtained by following Example 1 using the same fabric.

Similar results were obtained by using the following carriers:

Methyl p-tolyl sulfone p-Bromophenyl methyl sulfone 4-bromo-3-methylphenyl methyl sulfone p-Bromophenyl n-propyl sulfone Di-p-tolyl sulfone 4 p-Tolyl 3,4-xylyl sulfone p-Ethylphenyl-p-tolyl sulfone Bis 2,4-xylyl) sulfone p-Chlorophenyl phenyl sulfone p-Chlorophenyl p-tolyl sulfone 4-chloro-3-methylphenyl phenyl sulfone Bis (p-chlorophenyl) sulfone Bis 4-methoxy-3 -methylphenyl) sulfone Bis (p-methoxyphenyl) sulfone p-Acetamidophenyl phenyl sulfone Bis p-acetamidophenyl) sulfone Dibenzothiophene dioxide When the following dyes are substituted in Examples 1 and 2 similar results are obtained, i.e., the dyeing in the presence of carrier is always much stronger than that without carrier.

Blue, 1,4-diamino-N-(Z-hydroxyethyl)-2,3-anthraquinoncdicarboximide (US. 2,628,963)

Brown, The monoazo dye obtained by coupling the diazo of 2,6-dichloro-4-nitroaniline to N-ethyl-N(2-cyanoethyl-m-toluidine Example 3 The procedure of Example 2 is followed using as the carrier 4 parts of a diphenyl sulfone composition consisting of diphenyl sulfone, 1% sodium salt of technical lauryl sulfate, and 19% anhydrous sodium sulfate, which has been micropulverized to form a powder consisting of particles that will pass a ZOO-mesh screen.

When the acid-modified polyester fabric of Example 1 is dyed as described in Example 2 using the above dyebath, the resulting dyeing is one and three-fourths times as strong as the dyeing of Example 1.

Similar results are obtained when the lauryl sulfate used in this example is replaced by any surfactant including nonionics, anionics and cationics. The amount of surfactant employed is in the rangefof 0.1 to 5% by Weight of the sulfone carrier in the carrier composition.

Example 4 When the procedure of Example 2 is followed, using 50 parts of the diphenyl sulfone composition described in Example 3 as carrier, a dyeing is obtained which is five to six times as strong as that obtained in Example 1.

Example 5 A dyebath is prepared by dissolving 0.06 part of ap- (Z-cyanoethyl -methylamino] -phenyl} (o-chloropheny methane zinc double chloride, 0.06 part of bis(4-amino-m tolyl) (o-chlorophenyl)carbinol, 2 parts of the condensation product of 20 moles of ethylene oxide with one mole of a C alcohol, and 4 parts of the sodium salt of the condensation product of formaldehyde and 5,6,7,8-tetrahydro-Z-naphthalene-sulfonic acid in 4000 parts of water. The pH of the dyebath is adjusted to 5.0 by the addition of acetic acid or sodium carbonate as required.

parts of a fabric of acid-modified polyester fiber prescoured and rinsed as described in Example 1, is entered, while wet, into the dyebath. After dyeing at boiling temperature for one and one-half hours, the dyeing is rinsed and scoured as described in Example 1.

The resulting dyeing is a light blue shade.

spasyrre Example 6 A dyebath is prepared as described in Example 5. 20 parts of the diphenyl sulfone composition described under Example 3 are added, and the pH is adjusted to 5.0 as described in Example 5.

Fabric is entered, dyed and after-treated as described in Example 5. The resulting dyeing is a bright blue shade which is three times as strong as that obtained in Example 5.

Other sulfone carriers such as those listed in Example 2 may be substituted in this example with similar results.

Other cationic dyes which are suitable for dyeing acidmodified polyester fiber may be employed in this example. These include the dyes disclosed in U.S. 2,821,526 which are obtained by coupling a diazotized aminophenacylammonium salt with an aromatic amine. These dyes range from yellow to red in shade. The cationic red dyes disclosed in US. 2,888,467 may also be employed.

Example 7 A dyebath is prepared with 4000 parts of water. 2 parts of a long chain saturated hydrocarbon sodium sulfonate surfactant, 0.5 part of the condensation product of 20 moles ethylene oxide and 1 mole of a C alcohol and 1 part of the brown monoazo dye obtained by coupling the diazo of 2,6-dichloro-4-nitroaniline to N-ethyl-N(2-cyanoethyl)-m-toluidine. 100 parts Verel modacrylic fiber, a manufactured fiber in which the fiber-forming substance is any long-chain synthetic polymer composed of less than 85% but at least 35% by weight of acrylonitrile units which had been wet out with water, is entered and dyed for 2 hours at 160 F. The dyeing is rinsed and scoured with a solution of 0.5 part of the condensation product of 20 moles ethylene oxide with one mole of a C alcohol, and 4000 parts water for minutes at 160 F. The dyeing is then rinsed and dried. The fiber is dyed a very light tan shade.

Example 8 When Example 7 is repeated with a dyebath containing parts of the diphenyl sulfone composition described in Example 3 as a carrier, a light brown dyeing is obtained that is about four times as strong as that obtained in Example 7.

Example 9 A dyebath is prepared by mixing 1 part of the brown monoazo dye obtained by coupling the diazo of 2,6- dichloro-4-nitroaniline to N-ethyl-N(2-cyanoethyl)-mtoluidine with 6 parts of a long-chain saturated hydrocar- I bon sodium sulfonate surfactant and diluting with 4000 parts of water.

100 parts of a fabric of Kodel polyester fiber, a manufactured fiber in which the fiberforming substance is a long-chain synthetic polymer composed of at least 85% by weight of an ester of a dihydric alcohol and terephthalic acid (p-HOOCC H COOH), are prescoured 20 minutes at 180 F. in 4000 parts of a solution containing 2 parts of the sodium salt of the sulfate of the condensation product of ethylene oxide and oleyl alcohol, then rinsed, and entered, while wet, into the dyebath. After dyeing at boiling temperature for 1.5 hours, the fabric is removed from the dyebath, rinsed, scoured for 20 minutes at 180 F. with 4000 parts of solution containing 1 part of the prescouring surfactant, thereafter rinsed and dried. The resulting dyeing is a light brown shade.

Example 10 A dyebath is prepared as described in Example 9. 20 parts of the diphenyl sulfone composition described in Example 3 are added as carrier and stirred to give a uniform suspension.

100 parts of a fabric of Kodel polyester fiber prescoured as described in Example 9, are entered, dyed and after-treated in the manner of that example.

The resulting dark brown dyeing is about four times as strong as that obtained in Example 9.

Example 11 A dyebath is prepared by mixing 1 part of the brown reonoazo dye obtained by coupling the diazo of 2,6- dichloro-4-nitroaniline to N-ethyl-N(2-cyanoethyl)-mtol-uidine with 4 parts of thesodium sulfate of a longchain alcohol surfactant, and 4000 parts of water.

100 parts of a fabric of cellulose triacetate fiber, a manufactured fiber in which the fiber-forming substance is cellulose acetate and not less than 29% of the hydroxyl groups are acetylated, is entered into the dyebath and dyed at boiling temperature for 2 hours. The dyed fabric is removed from the dyebath, rinsed and scoured for 30 minutes at 180 F. with 4000 parts of a solution containing 1 part of the scouring agent described in Example 1 and 0.5 part of soda ash. The dyeing is rinsed and dried, and is light brown in shade.

Example 12 A dyebath is prepared as in Example 11,. 20 parts of the diphenyl suifone composition described in Example 3 are added and the mixture is stirred to a uniform suspension. A cellulose triacetate fabric is dyed and after-treated in the manner described in Example 11. The resulting dyeing is a brown shade which is one and one-half times as strong as that of Example 11.

Example 13 A dyebath is prepared in the manner described in Example 2 except that 10 parts of a carrier consisting of 7.5 parts diphenyl sulfone and 2.5 parts of benzanilide are used and that the fabric consists of 100 parts of polyethylene terephthalate, a manufactured fiber in which the fiber-forming substance is a long-chain synthetic polymer composed of at least by weight of an ester of a dihydric alcohol and terephthalic acid -nooc-cgr coon The resultant dyeing is a bright orange shade which is about four times as strong as a control dyed without carrier.

When the benzanilide in this example is either replaced or supplemented with 2.5 parts of dimethyl terephthalate, and 5' parts of diphenyl sulfone are used instead of 7.5 parts, similar results are obtained.

Example 14 A yarn composed of Vycron polyester fiber, a manufactured fiber in which the fiber-forming substance is a long-chain synthetic polymer composed of at least 85% by weight of an ester of a dihydric alcohol and terephalic acid (pHOOOC H COOI-I), is dyed in the same manner described in Example 7.

The resulting dyeing is a light brown shade.

Example 15 When Example 14 is repeated employing 20 parts of the diphenyl sulfone composition described in Example 3 as a carrier, the resulting dyeing is a dark brown shade which is about 8 times as strong as that from Example 14.

Example 16 A dyebath is prepared by mixing 1 part of the brown monoazo dye obtained by coupling the diazo of 2,6-dichloro 4-nitroaniline to N-ethyl-N(2-cyanoethyl)-m-toluidine with 4 parts of a long-chain saturated hydrocarbon sodium sulfonate surfactant and dispersing in 4000 parts of water.

parts of a fabric of Acrilan acrylic fiber, a manuwhich has been prescoured for minutes at 160 F. in a scouring solution as described in Example 1, and rinsed, is entered, While wet, to the dyebath and dyed for 1.5 hours at boiling temperature. The dyed fabric is removed, rinsed, scoured at 120 F. for 15 minutes with the same agent used to preseour, rinsed with water and dried.

The resulting dyeing is a light brown shade.

Example 17 When Example 16 is a repeated using parts of the diphenyl sulfone composition described in Example 3, as carrier in the dyebath, the resulting dyeing is a brown shade which is about three times as strong as that obtained in Example 16.

Example 18 Example 19 When Example 18 is repeated using 20 parts of the diphenyl sulfone composition described in Example 3 as carrier, the resulting dyeings are a brown shade which is three times as strong as those obtained in Example 18.

Example 20 A skein of regular Darvan nytril fiber, a manufactured fiber containing at least 85 of a long-chain polymer of vinylidene dinitrile (-CH C(CN) where the vinylidene-dinitrile content is no less than every other unit in the polymer chain, is prescoured at 180 F. for 15 minutes in an aqueous bath containing 2% of the condensation product of 20 moles ethylene oxide with 1 mole of a C alcohol and 2% tetra sodium pyrophosphate. The skein is dyed as described in Example 7, but after-treated according to Example 1. The resulting dyeing is a light brown shade.

Example 21 When Example 20 is repeated with 20 parts of the diphenyl sulfone composition of Example 3 included as a carrier in the dyebath, the resulting dyeing is a brown shade which is four times as strong as that from Example 20.

Example 22 A dyebath is prepared as described in Example 1, using 0.3 part of monochloro-4,8-diaminoanthrarufin instead of the azo dye described therein and, in addition, 20 parts of the diphenyl sulfone composition of Example 3 as carrier, on a scale where 1 part=0.7 gram.

The dyeing is run in a laboratory model beck dyeing machine which uses a strip of acid-modified polyester fabric as used in Example 1, said strip being 6 inches wide and 3 yards long and weighing about 70 grams. Said fabric has been prescoured and rinsed as described in Example 2 before it is put into the beck while still Wet.

After dyeing at a temperature of 206 to 210 F. for 1.5 hours, the fabric is removed and after-treated as described in Example 1.

The resulting dyeing is a bright blue shade which is equivalent to a control dyeing which uses 20 parts of sodium o-phenylphenolate tetrahydrate. The light fastness of the dyeing is much superior to that of the control.

When a portion of the dyeing and the control are each heat-treated for 1 minute at 400 F. and then exposed in the Fade-O-Meter, they exhibit similar light fastness which is, of course, vastly superior to that of the original control dyeing.

Example 23 The dyeing chamber of a package dyeing machine is loaded with parts of the acid-modified polyester fiber of Example 1 in rawstock package form and is rinsed by circulating water through the package and discarding it. The circulating bath is charged with 1 part of the condensation product of 20 moles of ethylene oxide and 1 mole of a C alcohol and 1500 parts of water which is maintained at 160 F. A slurry of 10 parts of the diphenyl sulfone composition of Example 3 in parts water is added to the circulating bath. The fluid from the bath is circulated through the package for 10 minutes at F. A solution of 3.0 parts of Cl. Basic Yellow 11 (CI. 48055), 0.4-5 part of Cl. Basic Violet 14 (CI. 42510), 1.0 part of CI. Basic Green 1 (CI. 42040), 0.3

y part of 0.1. Basic Blue 4 (Cl. 51004) is prepared in a minimum amount of glacial acetic acid.

This solution is diluted with water and sodium carbonate solution to give 140 parts of solution of pH 5.0. This dye solution is added to the circulating bath with enough Water to bring the total volume to 2000 parts. Circulation is continued at 160 F. for 10 minutes, and the dye liquor is heated to 206 to 208 F. Circulation at 206 to 208 F. is maintained for 2 hours, with the circulation direction being reversed every ten minutes.

At the end of this period the dyebath is withdrawn. A cold rinse is circulated through the package and drained.

The package is then scoured with 2000 parts of a solution containing 0.5 part of said ethylene oxide-alcohol condensation product for 30 minutes at 200 F. A water rinse is made and the package is dried.

The resulting dyeing is a full black shade which contains no significant amount of carrier powder.

A control dyeing made by the above procedure with the substitution of 4 parts of benzanilide and 4 parts of dimethyl terephthalate (US. 2,833,613) for diphenyl sulfone as carrier produces a similar shade, but the package contains crystals of the carrier.

Example 24 A bath is prepared using 20 parts of a diphenyl sulfone composition, as described in Example 3 (16 parts of sulfone), in 4000 parts water. 100 parts of the acid-modified polyester fiber of Example 1, and scoured in the manner described in Example 1, is treated in this bath for 1 hour at boiling temperature. The treated fabric is rinsed and scoured with 4000 parts of a solution containing 1 part of a condensation product of 20 moles of ethylene oxide and 1 mole of C alcohol for 5 minutes at 160 F. The fabric is rinsed and dried.

Analysis of this fabric showed a sulfur content of 0.76% while a control fabric similarly treated except for the absence of diphenyl sulfone contained 0.33% sulfur.

Vycron polyester fiber, a manufactured fiber in which the fiber-forming substance is a long-chain synthetic polymer composed of at least 85 by weight of an ester of a dihydric alcohol and terephthalic acid (p-l-IO0C-C H COOH) after treatment with diphenyl sulfone as described above, showed a sulfur analysis of 0.44% while the control showed 0.03%.

The diphenyl sulfone content of each of these fibers after the treatment is, by calculation, 2.9% and 2.8%, respectively.

The pretreated fabrics when dyed according to Example 1 show a color strength intermediate between the dyeings obtained in Example 1, without carrier, and those of Example 2, with carrier in the dyebath.

Since boiling water dissolves 0.5 gram/ liter of diphenyl sulfone, the 4 liters dissolve 2 grams. It has been found that significant dyeing improvements (rate, strength, levelness) are observed when the concentration of carrier is increased to about 2 grams per liter. The above results show therefore that under the conditions of this example, the 16 parts of diphenyl sulfone were divided, after 1 hour, as follows; 2 parts dissolved in water, 2.9 parts dissolved in the fiber and the remainder, 11.1 parts, was in suspension. Starting with 2 grams of carrier per liter, we might presume therefore that about 3 parts would remain in suspension.

An obvious equivalent of the fiber compositions obtained according to this example, is fiber which contains a sulfone carrier which is incorporated during the process of fiber manufacture.

Using the process shown in preceding Example 24, the following data were obtained which incorporate the figures given in that example. The time of heating is 1 hour in all instances.

TABLE I Concentration Diphenyl sulof Diphenyl tone entering Fiber sulfone in the fiber dyebath, percent by g./l. weight.

0.8 95 Polyester fiber 1 8. 4. 23 0. 8 0. :70 "Vicron polyster fiber 2:8 g: g

8.0 3. 9 0. S 1. 5 "Acrilan acrylic fiber 4. O 5.1 8. 0 5. 5 0. 8 1. 9 Arnel triacetate fiber 4. 0 10. 0 8. 0 10. 7 0v 8 0. 8 Durvan nytril fiber 4. 0 4. 7 8. 0 5. 9 0. 8 1. 6 Verel modacrylic fiber 4. 0 2. 6 8.0 3.0

When said Vycron, a manufactured fiber in which the fiber-forming substance is a l0ng-chain synthetic polymer composed of at least 85% by weight of an ester of a dihydric alcohol and terephthalic acid is heated with 8 grams/liter of diphenyl sulfone for 2 hours (instead of 1 hour), the additional 1 hour of heating increases the carrier content of the fiber from 3.9% to 4.7%.

Example 25 A dyebath is prepared using 0.3 part of the brown monoazo dye obtained by coupling 2,6-dichloro 4-nitroaniline with N-ethyl-l-I(2-cyanoethyl)-mtoluidine, 2 parts of the sodium salt of the condensation product of ethylene oxide and oleyl alcohol, 20 parts of the diphenyl snlfone composition described in Example 3 and 4000 parts water. The bath is adjusted to 120 F. and 100 parts of acidmodified acrylic fiber such as described in US. 2,837,500 and US. 2,837,501, which had been wet by boiling with water, is entered and dyed at boiling temperature for 1 hour. The dyed fabric is rinsed, scoured in 4000 parts of the scouring solution employed in Example 1 for 15 minutes at 180 F, rinsed and dried. Th resulting dyeing is light tan in shade and is about three times as strong as that obtained on a control in which no diphenyl sulfone is employed.

Example 26 When Zefran acrylic fiber, made by The Dow Chemical Company, is dyed according to the procedure of Example 25, a medium brown shade is obtained which is about 5 times as strong as that obtained in a control using no diphenyl sulfone.

Example 27 50 parts of methyl p tolyl sulfone (melting point, 89 C.) is mixed with 145 parts of water and 5 parts of the condensation product of 20 moles of ethylene oxide and 1 mole of a C alcohol. The mixture is warmed to C. and the liquid is agitated vigorously in a Waring Blendor until it is cooled to a paste.

A fabric of acid-modified polyester fiber is dyed in the manner described in Example 1 except that 20 parts of the above paste are employed instead of the 2 parts of ethylene oxide-alcohol condensation product. The dyed fabric is after-treated as described in Example 1, and a bright orange dyeing is obtained which is essentially the same strength as that obtained in Example 2 using the same fabric.

The X and Y substituents in the aryl ring of the sulfone carriers utilized according to this invention are not critical so long as water-solubilizing ionogenic groups are excluded.

The sulfone dye carriers should possess low solubility in water in order to promote mutual solubility of dye and fabric, and in order to assure favorable economics in view of the fact that saturated solutions containing suspended carriers are employed. The use of saturated solutions of carrier, in the presence of suspended carrier, assures a constant concentration of this agent during the dyeing operation and thus a relatively uniform dying. Using less than a saturated solution of carrier, the dyebath concentration decreases during the dying operation and the dye does not build up well on the fiber (poorer exhaust). A prefer-red concentration of diphenyl sulfone in the dyebath is 2.5 to 5.0 grams per liter. Low and high concentrations, respectively, are shown in Examples 3 and 4 (1 gram-10 grams per liter). The lower limit is 1 gram per liter. Diphenyl sulfone, for example, dissolves in cold water to the extent of 0.0013 gram per liter, whereas, it dissolves in water at C. to the extent of 0.5 gram per liter.

The solid sulfone carriers should be in finely divided form for best results. Recommended particle sizes are finer than 100-mesh and preferably finer than 200 mesh. Otherwise, the time required to reach equilibrium in the dyebath would become excessive. This compares with the carrier particle sizes disclosed in US. 2,833,613, col. 2, line 13 and in the examples.

Mixed carriers may be employed, e.g., mixtures of the sulfone carriers as well as mixtures of these with other types such as those described in U.S. 2,833,613. The use of mixed carriers is shown in Example 13.

Ml disperse dyes normally used for dyeing the hydrophobic fibers can be applied effectively with the sulfone carriers. The examples are only illustrative of the many disperse dyes used for this purpose.

Equivalent fibers for use in this invention includes those mixed fibers in which one or more of the disclosed hydrophobic fibers forms a part. Other fibers often mixed with these hydrophobics include wool, silk, cotton, nylon, cellulose diacetate, viscose rayon and the like.

The sulfone carriers are used to dye the hydrophobic fibers in light as Well as deep, level shades which possess the fully expected light fastness of the respective dyes on these fibers.

All of the requirements and advantages desired in a good carrier are realized. In addition to these advantages, a few corollary items have been observerd, e.g., (a) when dyeing mixed goods comprising hydrophobic fibers and wool with cationic dyes, less wool stain appears when a sulfone carrier is used. (b) The sulfone carriers provide brighter dyeings of disperse dyes on acid-modified polyester fibers as compared with the control dyeings made 1 1 in the presence of the dimethyl terephthalate and benzanilide carrier composition of US. 2,833,613.

A distinct advantage of the sulfone carriers over the carriers of said patent is noted in connection with the package dyeing process of Example 23. Although the patented carrier serves well in many applications, experience shows that it filters out of the dyebath during circulation of dye liquor in the package dyeing operation. The sulfone carrier, on the other hand, circulates through the package in uniform concentration without filtering out, notwithstanding the fact that it is not entirely in solution in the dye liquor.

Compared with the patented carrier, appreciably less sulfone-type carrier is needed for most dye applications. In many instances where disperse dyes are not easily dyed in level shades, the sulfone carriers effect outstanding improvement in levelness.

As many apparently widely difierent embodiments of this invention may be made without departing from the spirit and scope thereof, it is to be understood that this invention is not limited to the specific embodiments thereof except as defined in the appended claims.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. The process of coloring hydrophobic, acid-modified polyethylene terephthalate fibers with a cationic dye from a hot aqueous dyebath with the aid of a carrier, the improvement which comprises utilizing, as carrier, a sulfone compound selected from the group consisting of and 12 of H and CH and R is selected from the group consisting of a lower alkyl radical of 1 to 3 carbons and the radical sisting of in which sulfone compound X is selected from the group consisting of H, CH C H Cl, Br, OCH and NHCOR'; R is selected from the group consisting of CH; and C H Y is selected from the group consisting of H and CH and R is selected from the group consisting of a lower alkyl radical of 1 to 3 canbons and the radical References Cited in the file of this patent UNITED STATES PATENTS Hallada et a1. May 6, 1958 Kruckenberg Oct. 11, 1960 OTHER REFERENCES Schwartz et al.: Surface Active Agents, Interscience 45 Pub., Inc., New York 1949, vol. 1, page 91. 

1. THE PROCESS OF COLORING HYDROPHOBIC, ACID-MODIFIED POLYETHYLENE TEREPHTHALATE FIBERS WITH A CATIONIC DYE FROM A HOT AQUEOUS DYEBATH WITH THE AID OF A CARRIER, THE IMPROVEMENT WHICH COMPRISES UTILIZING, AS CARRIER, A SULFONE COMPOUND SELECTED FROM THE GROUP CONSISTING OF 